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941.
942.
It is very common to find meta-analyses in which some of the studies compare 2 groups on continuous dependent variables and others compare groups on dichotomized variables. Integrating all of them in a meta-analysis requires an effect-size index in the same metric that can be applied to both types of outcomes. In this article, the performance in terms of bias and sampling variance of 7 different effect-size indices for estimating the population standardized mean difference from a 2 x 2 table is examined by Monte Carlo simulation, assuming normal and nonnormal distributions. The results show good performance for 2 indices, one based on the probit transformation and the other based on the logistic distribution.  相似文献   
943.
A comprehensive meta-analysis of the validity of general mental ability (GMA) measures across 12 occupational categories in the European Community (EC) is presented. GMA measures showed that there is validity generalization and large operational validities for job performance and training success in 11 occupational groups. Results also showed that job complexity moderated the magnitude of the operational validity of GMA tests across three levels of job complexity: low, medium, and high. In general, results were similar to those found in the United States, although the European findings showed a slightly larger magnitude of operational validity in some cases. Theoretical and practical implications of these findings for personnel selection are discussed. ((c) 2003 APA, all rights reserved)  相似文献   
944.
The study explored the association between the perceptions 175 Chilean business students held about their parents' acceptance of academic dishonesty and their self-reports of academic dishonesty. Regressing scores for parental acceptance onto self-reported academic dishonesty indicated it accounted for a small (2.2%) but significant amount of variance beyond demographic and academic performance variables. Effect size analysis based on structure coefficients indicated that parental acceptance was the second best predictor in the equation, suggesting that parental acceptance is a correlate that merits further study.  相似文献   
945.
946.
947.
Surface color is traditionally measured by matching methods. However, in some conditions, the color of certain surfaces cannot be measured: The surface simply looks brighter or darker than all the patches on a matching scale. We studied the reliability, validity, and range of application of three different types of simulated Munsell scales (white-, black-, and split-surrounded) as methods for measuring surface colors in simple disk-ring displays. All the scales were equally reliable for matching both increments and decrements, but about 20% of the increments were unmatchable on the white-surrounded scale, about 13% of the decrements were unmatchable on the black-surrounded scale, and about 9% of the increments were unmatchable on the split-surrounded scale. However, matches on all the scales were linearly related. Therefore, it is possible to convert them to common units, using regression parameters. These units provide an extended metric for measuring all increments and decrements in the stimulus space, effectively removing ceiling and floor effects, and providing measures even for surfaces that were perceived as out of range on some of the scales.  相似文献   
948.
The effects of auditory context on the preattentive and perceptual organization of tone sequences were investigated. Two sets of experiments were conducted in which the pitch of contextual tones was varied, bringing about two different contextual manipulations. Preattentive auditory organization was indexed by the mismatch negativity event-related potential, which is elicited by violations of auditory regularities even when participants ignore the sounds (e.g., by reading a book). The perceptual effects of the contextual manipulations on auditory grouping were assessed using target-detection and orderjudgment tasks. The close correspondence found between the effects of auditory context on the perceptual and preattentive measures of auditory grouping suggests that a large part of contextual processing is preattentive.  相似文献   
949.
Neonatal handling is known to induce long-lasting changes in behavioral and neuroendocrine responses to stress. Since the central noradrenergic system participates in the adaptive responses to stressful conditions we have analyzed the effects of postnatal handling on beta-adrenoceptor binding sites and isoprenaline- and forskolin-stimulated cyclic AMP accumulation in cerebral cortex, hippocampus and cerebellum of rats at 1 and 3 months of age. Handled animals showed reduced emotional reactivity and lower ACTH and corticosterone secretion after stress. Binding studies using [(3) H]CGP12-177 revealed increased beta-adrenoceptor binding sites in handled rats in cerebellum and cerebral cortex with no changes in hippocampus, and decreased affinity in all cerebral regions. Handling reduced basal levels of cyclic AMP in hippocampus and cerebellum but not in cerebral cortex. The concentration-response curves of cyclic AMP to isoprenaline were displaced to the right in cerebellum of handled rats without differences in Emax; however, Emax was significantly reduced in cerebral cortex and hippocampus. Direct stimulation of the catalytic subunit of adenylyl cyclase by forskolin reduced the efficiency in hippocampus and cerebellum, but not in cerebral cortex of handled animals. It is concluded that neonatal handling reduces the binding properties of beta-adrenoceptor and its primary biochemical responses in the young rat brain, which may account for the reduced responsiveness to stress attained in the handled rats, and may explain the persistence of the effect. The present study emphasizes the role of the central noradrenergic system in modulating the behavioral and neurendocrine responses to neonatal handling.  相似文献   
950.
The current study examines teenage sexual behavior (in terms of having had sexual intercourse) as a function of sexual attitudes and sexual efficacy. At the heart of the study lies the assumption that sexual attitudes such as permissiveness are related to sexual behavior, but that this relation is stronger for sexually efficacious teenagers than for others. Using longitudinal data from 253 British adolescents, a structural equation model is tested and fit. The results provide partial support for the expectations, demonstrating the usefulness of sexual efficacy in predicting sexual behavior. Limitations and implications of the study are discussed.  相似文献   
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